1. Field of the Invention
The present invention relates to a method of manufacturing an electronic component having a capacitor element and a resistor element, a method of manufacturing a semiconductor device in accordance with the manufacturing method, and a semiconductor device obtainable by such method of manufacturing a semiconductor device. More specifically, the present invention is to make improvements in formation processes of a capacitor element and a resistor element, and can beneficially be applied to the field of electronic component or semiconductor device having a capacitor provided between electrodes made of a metal or the like, or having a resistor element provided between electrodes made of a metal or the like.
2. Description of the Related Art
A variety of electronic components having a capacitor element, or having both of a capacitor element and a resistor element have been known. A typical example thereof relates to a semiconductor device, such as LSI, having a capacitor element and a resistor element as passive elements.
An example of a conventional semiconductor device is shown in FIG. 10. On a substrate 3 made of, for example, silicon, interlayer insulating films 41, 42 are formed as stacked in this order, further thereon a first wiring 5 is formed, and still further thereon a second wiring 8 is formed as interposed by an inter-wiring insulating film 7.
In the conventional example shown now in the figure, a resistor element 2a is formed on the lower interlayer insulating film 41, where such resistor element 2a being connected to electrodes made of the same layer as the first electrode 5 so as to function as a resistor. On the other hand, a capacitor element 1a being a dielectric material is formed on the upper interlayer insulating film 42, where the capacitor element 1a is sandwiched by the first wiring 5 as a lower electrode and the second wiring 6 as an upper electrode, to thereby form a capacitor.
It has been a general practice that the capacitor element 1a and the resistor element 2a were formed independently using separate material layers as shown in the figure.
In the field of semiconductor device typified by LSI, recent trends relate to development of a variety of dielectric materials having a high dielectric constant in pursuit of further upgrading the degree of integration or capacitance of the capacitor element. Development activities are centered round dielectric materials such as Ta2O5, PZT, BST, STO or the like, and among which Ta2O5 (tantalum pentoxide) has already reached a phase of practical use, and introduction thereof into devices has already started.
By the way, SiN (silicon nitride), which is a typical conventional material for composing a capacitor element, has been considered to be beneficial in terms of load factor relative to facility investment, and in terms of additional value in the introduction into processes, since SiN is also applicable to various fields other than capacitor element such as device isolating material, protective film and so forth.
On the contrary, it is still not clear whether the all of the foregoing newly developed materials are always suitable for applications other than capacitor element. It may be sure that materials excellent as those for capacitor element are intrinsically valuable enough for memory LSIs whose additional value is defined by performance of the capacitor element per se. Development of such materials, however, does not always produce additional value when the materials are intended for use in electronic component such as a system LSI device, a mixed-signal LSI device and an MMIC device, in which the capacitor element is assumed as a part of passive elements. Thus it is not strictly meaningless to hesitate introducing such new materials when considering an overall additional value including improved capacitor performance over necessary process cost and facility introduction cost.
Thus the present inventor has long been investigating into a material excellent as that for the capacitor element and suitable for other applied fields, and also into whether it is possible to provide a simple technique based on a proper use of such materials.
It is therefore an object of the present invention to find out a material excellent as that for the capacitor element and suitable for other applicable fields, and to provide a technique for obtaining an electronic component in which such material can fully exhibit its advantage in such applications.
To accomplish the foregoing object, the present invention employs a specific material which can produce both of a capacitor element and a resistor element when locally subjected to different kinds of treatment.
The present invention was proposed basically in the course of searching a material suitable not only for a capacitor element but also for applications other than the capacitor element, where such material should be made applicable to a plurality of applications by one or more proper treatment processes, and where an application other than the capacitor element being assumed as a resistor element. The present invention is based on findings the present inventor obtained from the above search efforts.
The present invention is to provide a method of manufacturing an electronic component having a capacitor element and a resistor element, and is characterized in that the capacitor element and the resistor element are individually formed in the same material layer initially having a single composition by locally subjecting the material layer to different kinds of treatment. Also the present invention is to provide a method of manufacturing an electronic component having a capacitor element and a resistor element, and is characterized in that the capacitor element and the resistor element are individually formed by introducing into a tantalum oxide film oxygen within an area for forming the capacitor element, and nitrogen within an area for forming the resistor element, respectively.
A method of manufacturing a semiconductor device of the present invention is to provide a method of manufacturing a semiconductor device having on a single substrate a capacitor element and a resistor element, and is characterized in that the capacitor element and the resistor element are individually formed in the same material layer initially having a single composition by locally subjecting said material layer to different kinds of treatment. Also the present invention is to provide a method of manufacturing a semiconductor device having a capacitor element and a resistor element, and is characterized in that the capacitor element and the resistor element are individually formed by introducing into a tantalum oxide film oxygen within an area for forming the capacitor element, and nitrogen within an area for forming the resistor element, respectively.
Furthermore, a semiconductor device of the present invention relates to the one having a capacitor element and a resistor element in a single substrate, and is characterized in that the capacitor element and the resistor element are individually formed in the same material layer initially having a single composition by locally subjecting said material layer to different kinds of treatment.
According to the present invention, the capacitor element and the resistor element are formed by separate treatments on a single material layer, that is, one material is used not only for the capacitor but also for the resistor. This can realize additional value of the development and ensure an efficient device formation.
For instance, Ta (tantalum) which has been developed as a typical high dielectric material is known to become an insulating material after being oxidized, and to become an electro-conductive material suitable for use as a resistor after being nitrided. Based on such property, forming process of tantalum compound (Ta2O5) layer can add its value (performance/cost ratio) by forming a capacitor element and the resistor element in the same layer. Such a case is also advantageous in that shrinking, downsizing and higher integration of the device since a tantalum nitride resistor can achieve high sheet resistance relatively easier than a conventional resistor does.
Similar effects are obtainable also with other materials provided that they can be a capacitor element and a resistor element depending on the treatments.
According to the present invention, a material excellent as that for capacitor element and also suitable for other applications is used, and the material is effectively converted into other materials suitable for the capacitor element and resistor element, respectively. Thus the present invention can add further value of such material, and allows a positive attitude to be taken in facility investment for such material and introduction of other similar new materials.